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Finding the Fourth Proportional to 517.89, 776.73 and 431.78

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Solution

The fourth proportional to 517.89, 776.73 and 431.78 is: 647.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    517.89 : 776.73 = 431.78 : x
  2. Step 2: Convert to fraction form
    517.89/776.73 = 431.78/x
  3. Step 3: Cross multiply
    517.89x = 776.73 × 431.78
  4. Step 4: Simplify right side
    517.89x = 335,376.48
  5. Step 5: Solve for x
    x = 335,376.48/517.89
  6. Step 6: Final answer
    x = 647.58

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.